AT 1545C,759MP REPORTS ENGAGING A LN VEH IVO BAGHDAD, ZONE 25, MB42007790. A BLACK FOUR DOOR BMW APPROACHED AT A HIGH RATE OF SPEED TO THE REAR OF THE CONVOY. THE GUNNER USED HAND/ARM SIGNALS TO WAVE OFF THE VEHICLE TO NO AVAIL. THE GUNNER FIRED ONE M9 ROUND ON THE GROUND IN FRONT OF THE VEH AT WHICH TIME THE VEH MOVED BACK TO A SAFE DISTANCE.